U.S. patent number 4,095,371 [Application Number 05/825,346] was granted by the patent office on 1978-06-20 for operating mechanism for box car sliding doors.
This patent grant is currently assigned to Pullman Incorporated. Invention is credited to Willis H. Knippel.
United States Patent |
4,095,371 |
Knippel |
June 20, 1978 |
Operating mechanism for box car sliding doors
Abstract
A cable drive mechanism for opening and closing a sliding box
car door includes a high friction drive pulley carrying a cable
which is anchored at opposite ends to the sides of the box car and
a low friction guide pulley which is in aligning relation to the
drive pulley. The drive pulley is manually rotated for sliding the
box car door between open and closed positions.
Inventors: |
Knippel; Willis H. (Palos Park,
IL) |
Assignee: |
Pullman Incorporated (Chicago,
IL)
|
Family
ID: |
25243779 |
Appl.
No.: |
05/825,346 |
Filed: |
August 17, 1977 |
Current U.S.
Class: |
49/352; 49/220;
49/360 |
Current CPC
Class: |
E05F
11/53 (20130101); E05Y 2900/132 (20130101) |
Current International
Class: |
E05F
11/00 (20060101); E05F 11/53 (20060101); E05F
011/00 () |
Field of
Search: |
;49/352,360,220,218
;160/279,277 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Kannan; Philip C.
Attorney, Agent or Firm: Anderson; Thomas G.
Claims
What is claimed is:
1. For a railway car having a side door opening and a sliding door
laterally movable from said opening to one side thereof, said door
and car including releasable inter-engaging locking mechanisms, the
improvement of a cable drive mechanism for opening and closing said
door comprising;
a first drive pulley rotatably connected to said door,
a second guide pulley rotatably connected to said door adjacent to
said first pulley,
a third idler pulley arrangement connected to said door for
rotation above said first and second pulleys,
said third pulley arrangement including a pair of circumferentially
extending first grooves,
a cable including means on one end for fixedly connecting the same
to said car on one side of said door,
said cable extending around one of said first grooves to said first
and second pulleys and around the other of said first grooves of
said third pulley arrangement,
said cable including a second end extending from said third pulley
arrangement and including second means fixedly connecting the same
to said car on the other side of said door.
2. The invention in accordance with claim 1,
said means fixedly connecting said cable ends including biasing
means for maintaining tension on said cable ends.
3. The invention in accordance with claim 2,
said tension means comprising springs.
4. The invention in accordance with claim 1,
said first drive pulley being constructed and arranged to have a
high coefficient of friction, and said second guide pulley
arrangement having a low coefficient of friction.
5. The invention in accordance with claim 4,
said first drive pulley comprising polyurethane and said second
guide pulley comprising polyethelene.
6. The invention in accordance with claim 4,
said first and second pulleys each having a plurality of
circumferentially extending third and fourth grooves around which
said cable extends.
7. The invention in accordance with claim 6,
said grooves of said first and second pulleys being equal in
number.
8. The invention in accordance with claim 1,
said guide pulley being rotatably supported on said door by rigid
shaft means,
a sprocket on said shaft,
hand wheel means connected to said sprocket to rotate the same,
said drive pulley being supported on said door by second rigid
shaft means,
a second sprocket on said second shaft means connected to said
drive pulley to rotate the same, and
a drive chain connecting said sprockets.
9. The invention in accordance with claim 8,
said guide pulley being vertically positioned above said drive
pulley.
10. The invention in accordance with claim 8,
said drive pulley and guide pulleys each comprising a plurality of
grooves and said drive pulley having enlarged outer peripherally
and circumferentially extending flanges.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to sliding box car doors and
specifically to the type of door which is manually power operated
for sliding the door between open and closed positions.
2. Description of the Prior Art
The prior art is exemplified in U.S. Pat Nos. 1,503,500, Aug. 5,
1924; 233,658 Oct. 26, 1880; 2,841,390 July 1, 1958; 3,720,020 Mar.
13, 1973; 3,816,965 June 18, 1974; 3,913,267 Oct. 21, 1975 and
3,913,268 Oct. 21, 1975.
SUMMARY OF THE INVENTION
The present invention relates to a sliding box car door which is
operated by a cable drive mechanism to slide the door between open
and closed positions. Such cable mechanisms are shown in the
aforementioned patents and operate in response to the manual
manipulation of a hand wheel by an operator standing on the ground
adjacent to the box car. In the present invention, as in the prior
art, the cable ends are connected to opposite ends of the box car
and are directed downwardly to a cable drive mechanism by means of
idler pulleys supported on top of the sliding door. The manually
operated drive mechanism of the present invention includes a hand
wheel which is rotatably supported on the outer surface of the
sliding door and which is connected to rotate a drive pulley
contained within a door housing which also is in adjacent spaced
relation to a guide pulley. The cable of the mechanism is wound
about the guide pulley and drive pulley by a number of wraps so as
to provide a means of steering the cable around the pulleys so that
alignment and positive action of the cable is achieved. The present
arrangement provides for a 5:1 ratio of mechanical advantage of the
cable drive with respect to the door construction. The arrangement
of the guide pulley and relationship to the drive pulley eliminates
the possibility of the cable climbing on the drive pulley. This is
one of the advantages over the prior art. Also, the guide pulley is
made of a low friction polyethelene material whereas the drive
pulley includes a high friction polyurethane material. This
arrangement permits the cable to slip on the guide pulley without
simultaneously slipping on the drive pulley. Therefore any slack
between coils wrapped on the drive pulley will be automatically
eliminated during the operation of the device. The feature insures
uniform cable distribution on the drive pulley surface which
similarly is an improvement in cable drive mechanisms.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a railway box car showing a
sliding door arrangement;
FIG. 2 is an enlarged side elevational view of a portion of the box
car shown in FIG. 1 disclosing the sliding door;
FIG. 3 is a cross-sectional view taken substantially along the line
3--3 of FIG. 2;
FIG. 4 is a cross-sectional view taken along the line 4--4 of FIG.
3;
FIG. 5 is a detailed view showing the connection of a cable end to
the sides of a box car;
FIG. 6 is an end elevational view taken along the line 6--6 of FIG.
5;
FIG. 7 is a schematic view disclosing a pulley arrangement of the
present invention;
FIG. 8 is a cross-sectional view of another modified embodiment of
the invention;
FIG. 9 is a cross-sectional view taken along the line 9--9 of FIG.
8; and
FIG. 10 is a cross-sectional view taken substantially along the
line 10--10 of FIG. 8.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1 and 2 disclose a railway car 10 comprising a conventional
underframe 11, car trucks 12 and car sides 13. The car includes end
walls 13' and a roof structure 14. A door opening frame 15 defines
a door opening 16 which is closed by a first sliding door 17 and a
second sliding door 18. The first sliding door 17 is a
comparatively narrow door and includes an inter-engaging locking
mechanism 19 which is adapted to interlock with the door 18 for
movement therewith as desired. The door 17 also includes roller
assemblies 20 which suitably support the door 17 for sliding
arrangement on a track 21 suitably supported on the sides of the
car below the door opening. The second sliding door 18 also is
provided with similar roller assemblies 22 and includes a hand
wheel 23 which operates a suitable linkage arrangement 24 for
pivoting an operating rod 25 which by means of crank arms 26, one
of which is shown, is supported on one of two roller assemblies 22
which provide for outward movement and relative sideway sliding
movement of the door on the track 21. Locking bolts 27 are also
actuated by the hand wheel 23 for locking the door assembly in a
closed position. The operating arrangement for locking and moving
the doors is more specifically disclosed in patents 3,816,965;
3,913,267 and 3,913,268.
A cable drive operating mechanism is generally designated at 30 and
includes a U-shaped metal enclosure or housing section which is
suitably connected to the side of the second door 18. The housing
section 31 is supported at its lower end by means of a horizontally
extending lower flange 32. The section 31 includes vertical side
plates 33. A U-shaped housing section 35 includes a front vertical
plate 34 which with the housing section 31 provides an enclosure
within which the door operating mechanism 30 is positioned. The
housing sections 31 and 35 are suitably supported on spacers 36
provided on the door 18. Pivot shafts 37 and 38 are also supported
on the door 18 by means of the U-shaped section or plate 35 which
is rigidly connected to the door 18. A guide pulley 39 is pivotally
supported on the shaft 37 and is spaced from the plate section 35
by means of a spacer plate 40. The guide pulley 39 includes a
plurality of circumferential grooves 41 and is rotatably supported
on the shaft 37 and retained thereon by means of a retainer plate
78.
As best shown in FIG. 3 a drive pulley 54 is rotatably supported on
the lower shaft 38. The drive pulley 54 includes a hub 47 in
bearing relation to a spacer plate 43 positioned on the shaft 38. A
retainer plate 44 secures the hub 47 for rotation on the shaft 38.
The drive pulley 54 includes a cylindrical body plate 77 which
supports a plurality of circumferentially disposed bolts 60
extending through spacers 49 and secure to a hand wheel 52 by means
of a plurality of nuts 61.
As best shown in FIGS. 1, 5 and 6, cable connections 66 are
provided at opposite ends of the box car adjacent to the roof ends
thereof. Each cable connection includes a rod 67 which is slidably
disposed in a bracket 65 secured to an outwardly and downwardly
projecting portion of the roof 14 as indicated at 64. The rod 67 is
provided with a spring retainer disc 69 which holds captive between
the bracket and said disc a spring designated at 70. The end of the
one end of the rod 67 is provided with a hook eye 68 to which a
cable 71 is connected. The cable extends from the connections 66
inwardly and are wrapped on to the idler pulleys 76 which are
freely journaled on a shaft 73 supported on the door 18. The upper
end of the door is provided with a horizontal channel 72 providing
a top beam for said door. The channel 72 is suitably apertured as
indicated at 74 to provide for rotational clearance of the idler
pulley arrangement 75. The pulleys 76 are freely journaled on the
shaft 73 and the cable extends downwardly as indicated at FIG. 3 is
wrapped around portions of the guide pulley 39 and is suitably
wrapped about the drive pulley 54.
FIGS. 8, 9, and 10 disclose a modified form of the invention
wherein the drive pulley is supported on the shaft 37 and thus is
positioned on the same shaft that the idler pulley 39 is
positioned. In FIG. 8 the shaft 37 is somewhat longer in length in
order to support the hand wheel 52 and associated sprocket
arrangement as will be described. The drive pulley 54 and
associated parts of the embodiment shown in FIG. 8 is substantially
similar to the arrangement shown in FIG. 5 and where the parts are
substantially similar the same reference characters are applied.
Referring to FIG. 8 the hand wheel 52 is supported by means of a
bearing 42 on the shaft 37 and in turn supports the sprocket
carrier 45. The sprocket 45 includes a hub 47 having supported
thereon a sprocket 46 for rotating the same. The sprocket carrier
47 includes the hub 45 which is spaced from the guide pulley 39 by
means of a spacer plate 43. A retaining plate 44 retains the
sprocket carrier 45 on the shaft 37. The hand wheel 52 is secured
to the sprocket carrier 45 by means of spacers 49 and bolts 50 and
nuts 51. Thus rotation of the hand wheel provides for rotation of
the sprocket while the guide pulley 39 can swivel freely in an
idling manner with respect to the rotation of the hand wheel 52.
The hub 47 is connected to a hub plate 48 of cylindrical shape to
which the hand wheel 52 is connected as described before. In the
latter arrangement the hand wheel 52 is disposed above the drive
pulley 54 which is driven by means of the sprocket and chain
arrangement 63 which is disclosed in FIG. 8.
OPERATION
The operation of the cable drive mechanism as shown in FIGS. 1, 2
and 3 is achieved when the door 18 alone or in unison with door 17
is to be moved laterally outwardly of the door opening to an open
position. The power arrangement for moving the door requires the
operator to turn the hand wheel 52 which rotates the drive pulley
54 in turn occasioning the winding of the cable on the guide pulley
and idler pulleys to move the door laterally placing tension on one
side of the cable and providing a slack on the other side of the
cable. The movement of the cable thus is conventional in the prior
art in response to the rotation of a suitable wheel and drive wheel
arrangement. In the present instance the advantages of the
invention are achieved in that the drive pulley is of a high
friction type having been constructed of high friction polyurethane
whereas the low friction guide pulley is constructed of a material
known as polyethylene.
The guide wheel structure of the present invention thus in
combination with the drive pulley provides for maximum contact
between the cable and the surface of the drive pulley by
eliminating the possibility of the cable climbing on itself. Since
the magnitude of the frictional engagement force between the drive
pulley and the cable is related to the extent of the pulley surface
contacted by the cable this feature provides for an improved and
more efficient cable driving mechanism.
Further by the utilization of the differential of high friction and
low friction with respect to the associated pulleys the guide
pulley allows the cable to slip on the guide pulley without
simultaneously slipping on the drive pulley. Therefore any slack
between the cable and the cable coils wrapped on the drive pulley
will be automatically eliminated during operation of the device.
This feature thus insures uniform cable load distribution on the
drive pulley surface which similarly is an improvement in the cable
drive mechanism. In the modification shown in FIGS. 8, 9 and 10,
the hand wheel is positioned above and on the same shaft 37 as the
guide pulley 39. In this connection, rather than a direct
connection of the wheel to the drive pulley 54, the hub and
sprocket carrier arrangement support the drive wheel and by means
of a sprocket and chain arrangement the drive pulley 54 which is
disposed below on a shaft 38 is rotated in operational manner. The
advantages enumerated above with respect to the high friction and
low friction of the drive pulley and guide pulley are the same and
the rest of the advantages disclosed in the invention are available
with both types of devices. It is to be noted that the grooves of
the drive pulley and guide pulleys are concentric and that in each
instance one of the pulleys is power driven. Further advantage in
the drive pulley is provided by the outer enlarged peripherally
extending and circumferential flanges 56 which also serve in the
alignment and friction drive of the cable in winding of the cable
on to cable turns on to each other. The cable movement is
controlled therefore by friction between the drive and guide pulley
grooves. The driving force which is achieved is dependent on the
difference between tension in the tight and slack side. In order to
avoid unequal tensions or differential actions between various
wraps of cable the high friction polyurethene drive pulley with the
low friction polyethylene guide pulley is provided. Additional
advantages result that the grooved pulleys eliminate the crowding
climbing action found in other types of sheave arrangements. A
better slip clutch action is also obtained for positive overload
protection under all conditions. The units also are adapted to fit
within a relatively small space and thus are more easily installed
and at a relatively more inexpensive cost.
* * * * *